Keynesian concepts of probability and uncertainty emphasize the basis of knowledge available to economic decision makers. Conditions of uncertainty, which involve missing evidence or doubtful arguments, are distinguished from probable risk. Beyond this, on the basis of the claim that the future is yet to be created, some authors argue for further distinctions among different kinds of uncertainty. The paper reviews this particular argument, distinguishing it from Keynesian uncertainty theory generally, and provides a critique of its implication that, due to innovation, objective distributions of possible events do not generally exist at the time of economic decisions.